Apple’s OS X Lion is available today which is big news on its own, but the company’s push for digital delivery through the Mac App Store is a very interesting underlying story. Rather then buying the OS update from retailers or from brick-and-mortar Apple stores, the 3.7GB file will predominantly be sent out through Apple’s servers, just like any other Mac app.

Apple is incentivizing the move away from physical media by pricing the digital copy at just $29.99 and making purchases quick and easy for Snow Leopard users, who are by now already familiar with the App Store. Despite the massive amount of data Apple must be moving, downloads are going smoothly and moving along at a pretty reasonable clip (from what we’ve seen).

Of course a 4GB download isn’t great news for everyone–users who don’t have broadband or on metered accounts are out of luck for launch day purchases. Apple has noted that users that are unable to download the software will be able to buy the upgrade on a USB drive for $69.99 “later this August”. That way they will have a physical copy and no downloading will be necessary, but some extra cost will be involved.

The other option Apple floats is that buyers will be able to visit an Apple store and download it there. This probably means just hopping on their network and downloading, or possibly using one of their USB copies to install and then just getting your own serial.

So why charge $40 for a 4GB USB drive? Foremost, the price differential will discourage people from buying the USB copy. Plus we can be sure that Apple wants to promote usage of the Mac App store. Once you buy a $30 OS upgrade with that account you’ll a) know how to use the store b) your account will be setup c) you’ll have an account you’ll want to retain with something valuable in it. Apple gets the secondary benefits of having your information on file and not having to split the profits with any sort of middleman.

The download took me a little under 2 hours (see below), which isn’t long to wait for an OS update. It’s definitely a good way to go if bandwidth isn’t an issue, but it won’t be possible for everyone. If you’re not a broadband user then consider a trip to your local Apple store or you can always find a place with fast WiFi where you can camp out for a bit and download it. The USB copy of Lion will be a last resort, but for some people it will be useful–even in the age of digital delivery some people still need old fashioned delivery methods to get the job done.